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About peterh

  • Rank
    Advanced Member

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  • Bike
    JGas 250 and others.

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  • Location
    Western Australia
  • Gender
  1. To close off and thank for suggestions, I have settled on 45 pilot and 125 main with needle clip on 4th groove down - for sealevel and daytime temps ~20°C (autumn in Western Australia). Air Screw is 1 turn out. Runs crisp and clean throughout throttle range.
  2. Reed effects on engine character

    I have fitted boyesen dual stage reeds to 2010 Evo 125, a 2012 Evo 200 and my 2014 and 2015 Jotagas 250. I haven't used the carbon reeds so cannot compare. Once jetting is optimised (and yes had optimised settings of the carbys with standard reeds before i decided to change), i have found that on all 4 bikes that, in my opinion, there is better stable idle and off idle, an improvement in ability to pull smoothly from low down but also a crisper response throughout the range. By reading the boyesen material the dual stage suit my riding. I dont do splat walls that maybe the carbon reeds would give better top end but i relish the smooth, slow climb, turn and then double blips up and over logs, rocks etc. I think the bike that benefitted by the boyesen reeds most noticeably was the Evo 125, it seemed to give the 125 a lot more low down pull and smooth uptake rather than just have to rev the 125. I admit that with the 2015 jotagas i also changed the dellorto to a oko 26mm and a 5mm inlet manifold spacer at the same time as putting in the boyesens, so cannot be sure what the single effect of the boyesens were on that bike.
  3. Thanks copemech - I might start with what the 2016 specs say and go from there.
  4. Hi, I am the new owner of a 2nd hand 2015 ST125 and yes it is a 2015 model. I am looking for the standard jet specifications for a 2015 Sherco ST125 with a Keihin PWK28 carby. The Owners Manual (hardcopy and those downloaded from Sherco manufacturer and agents sites) give details for a Dellorto for that year for the 125, but the advertising brochure says it is a Keihin PWK28 and the parts book gives both dellorto and keihin parts and various jet sizes. And I am told only the 250 came with the Dellorto in that year. I can find the standard specifications for the 2016 ST125 but would like to check the current carby against the standard specifications for slow, main and clip position on the JJH needle for the 2015 model. Any help is appreciated.
  5. Gear oil what flavour do i use?

    To add to the theme, i use Mohican Chief Oil ATF Dexron III which has viscosity specifications at 40°C and 100°C and a Viscosity Index almost identical to very popular and well known trials transmision brands but pay AUD $30 for 4litres from Supercheap versus the same cost for 1litre for a trials specific gear oil. Makes doing regular changes very economical. And no, despite what you may be thinking on the theme name, Mohican Chief oil is not North American but is from the Netherlands. Almost opposite Downunder.
  6. Kill switch oset

    Looking at the wiring diagram in the manual that i found online, it does appear the same as in the video. You could/should check with your oset dealer if you have one close.
  7. Kill switch oset

    Have a look at this youtube video - is this the information that you are needing?
  8. Serial # help required

    Hi - I'm from Aus (WA) and have a 2015 JGas 250. I suggest you contact Paul Arnott from TheHellTeam as he would have imported and likely sold the bike originally. I had a look at that on Gumtree (my 2014 Jotagas is up there as well). The bike you are looking at certainly looks to have the specs of a 2015 Jotagas with the Elka Shock but may have a later sticker set than mine - looks to be an S3 set. Also looks to have the thicker bash plate than the original 2014 and 2015 bikes. Also the VIN number gives it as a 300cc and looking at the 115 number is similar to my 2015 bike while my 2014 Jotagas had 114. So to me it is a 2015 JGas 300. Cheers Peter
  9. 2018 Jotagas????

    Well at long last their website is back on-line. Nice pics of the 2017 bike.
  10. 2012 Sherco ST290 Bog and Smoke

    There is some good information above - see beta-blocker. With regard Maxima 927, I too use Maxima 927 and researched it before decision to use. Yes, there is past history of sticking ring grooves etc etc but reading (yes, from the manufacturer who acknowledges that history) these issues may well be past history. I converted to Maxima 927 18 months ago after a long history of using two well known brands used in trials bikes. Why did I investigate and change - some of it was "advice" given by others that they would never use X brand because someone they knew seized their engine and then for the other brand having pulled apart my motor for another reason (one ball bearing delaminating in a well known and respected bearing manufacturer in an engine lubricated by a well respected transmission oil for trials bikes) I found the piston crown with a hard encrusted black carbon, compression dome similarly encrusted and rings and ring grooves horribly gummed up having used a common respected trials pre-mix oil at 100:1 (as recommended by the factory). After much research and some discussion with others, I converted to Maxima 927. Find attached images of my piston crown and the compression dome after 18 months of use (~100 hours of riding) since previous tear-down (pics taken through the spark plug and by a USB micro camera pointed up from the exhaust port. To be able to still see the size of the piston (see attached image) and, in other pics I have, to see the manufacturing date etc of the piston and to see the clean compression dome (see attached) gave me confidence to continue. As I had the exhaust off (I needed to get the bash plate off) I also took pics of the rings & grooves through the exhaust and they were also very clean (unfortunately I must have deleted them). I use 80:1 pre-mix, (no more than 5L mixed at a time), the plug is a coffee brown colour and I have spent time on carburation and not over-oiling air-filter and my exhaust header did not appear any blacker or encrusted than I have had in the past. The downside is that I cannot use anyone else's synthetic fuel if I run out - the upside, they cannot borrow mine. So, while there is a perhaps history for those using castor based oil including gumming up rings and grooves, that may not appear to be the current state of affairs, perhaps things have moved on - after all, I started riding trials when 25:1 or 32:1 was standard and using 50:1 was "way out there" in an aircooled engine. I have obviously moved on.
  11. Carb to disc inlet rubber

    If it is just a split without too much related deterioration there are specific super glues eg. Loctite make several ones that can withstand high temp, and vibration and have flexibility for rubber. Just a thought - short term or potentially long term.
  12. G2 Parts For Jotagas

    And they look good on the pics published of the 2017 model.
  13. Inner Sole

    I have recently started to use a pair of generic orthotics in my Forma boots - https://www.homyped.com.au/shop/inserts/full-orthotic-insert/ (after removing the simple foot insert) and while initially I felt they increased my height on the pegs, I have got used to them and find them very comfortable and less achy feet at end of the day (I have fairly flat feet). Being firm they provide good support. They are leather topped and I have got them soaking wet. Took them out, put them between layers of paper in the sun warmth and they are as good as new. So, something to consider.
  14. I wear bifocals all the time as cannot tolerate the varifocal type lens. The bifocals give me the distance and the fine reading, which is what i use when riding. I also have a pair that are bifocal for mid range and reading e.g. good for work on the computer and reading but also great for working on the bike and then on the bench e.g. taking the carby out and then reading the jet sizes. Have been thinking about trying these http://www.neweyeco.net where you have a prescription insert that you can swap in and out of different frames including safety glasses.
  15. Brakeless

    Perhaps suggest to FIM for World Trials Championships to help with no-stop rules?